<template>
  <div>
    <div class="photoTips">
      <p>人脸照片录入注意事项：</p>
      <p>1、尽量选取光线充足的地方进行拍照；</p>
      <p>2、拍照过程中将美颜功能暂时关闭；</p>
      <p>3、只拍取上半身的相片，提高识别度。</p>
    </div>
    <div v-if="headerImage">
      <img :src="headerImage" style="height: 8rem;width: 11rem"/>
      <div>
        <a href="javascript:void (0)" @click="reset" class="weui-btn weui-btn_mini weui-btn_warn">重置</a>
        <a href="javascript:void (0);" @click="upload" class="weui-btn weui-btn_mini weui-btn_default">上传</a>
      </div>
    </div>
    <div v-if="!headerImage" class="oh">
      <div class="cameraIcon">
        <img src="../../static/img/tianjia2.png" @click="fileInputFn" style="width: 8rem;height: 8rem;">
      </div>
      <input ref="fileInput" type="file" name="" id="" accept="image/*" @change="uploadFile"
             style="position: relative;left: 99999999999px;">
    </div>
  </div>
</template>
<script>
  import Exif from 'exif-js';
  import $ from 'jquery';

  export default {
    name: 'photograph',
    data() {
      return {
        headerImage: '', // 展示头像
        avatarFile: '', // 头像
        cos: null,
        options: {
          bucket: '',
          region: '',
          folder: '',
          domain: '',
        },
        user: {
          id: '',
          loginType: ''
        }
      };
    },
    methods: {
      fileInputFn() {
        this.$refs.fileInput.click();
      },
      getCosCredential() {
        let that = this;
        that.$http.getCosCredential().then(resp => {
          this.options = resp.data;
        });
      },
      dataURLtoFile(dataurl, filename) { //将base64转换为文件
        var arr = dataurl.split(','),
          mime = arr[0].match(/:(.*?);/)[1],
          bstr = atob(arr[1]),
          n = bstr.length,
          u8arr = new Uint8Array(n);
        while (n--) {
          u8arr[n] = bstr.charCodeAt(n);
        }
        return new File([u8arr], filename, {
          type: mime
        });
      },
      reset() {
        this.headerImage = '';
        this.$emit('reset-file');
      },
      upload() {
        let fileName ="face_"+ this.uuid() + '.jpg';
        let file = this.dataURLtoFile(this.headerImage, fileName)
        this.$toast.show('上传中...', 'loading');
        let formData = new FormData();
        formData.append('file', file);
        formData.append('key', fileName);
        formData.append("token", this.options.token);
        let that = this;
        $.ajax({
          url: this.options.uploadServer,
          type: 'post',
          data: formData,
          processData: false,
          contentType: false,
          success: function (resp) {
            that.$emit('accept-file',fileName);
            that.$weui.toast('上传成功');
          }, error: function (resp) {
            that.$weui.toast('上传失败');
          },
          complete: function () {
            that.$toast.hide();
          }
        })
      },
      // 上传文件
      uploadFile(e) {
        // this.avatarFile = e.target.value
        let files = e.target.files || e.dataTransfer.files;
        if (!files.length) return;
        this.avatarFile = files[0];
        this.imgPreview(this.avatarFile);
      },
      uuid() {
        let date = new Date();
        function S4() {
          return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
        }
        return (date.getFullYear() + "" + (date.getMonth() + 1) + S4() + S4() + S4() + S4() + S4() + S4());
      },
      imgPreview(file) {
        let self = this;
        let Orientation;
        // 去获取拍照时的信息，解决拍出来的照片旋转问题
        Exif.getData(file, function () {
          Orientation = Exif.getTag(this, 'Orientation');
        });
        // 看支持不支持FileReader
        if (!file || !window.FileReader) return;
        if (/^image/.test(file.type)) {
          // 创建一个reader
          let reader = new FileReader();
          // 将图片2将转成 base64 格式
          reader.readAsDataURL(file);
          // 读取成功后的回调
          reader.onloadend = function () {
            let result = this.result;
            let img = new Image();
            img.src = this.result;
            // 判断图片是否大于100K,是就直接上传，反之压缩图片
            if (this.result.length <= 100 * 1024) {
              self.headerImage = this.result;
              // self.postImg();
            } else {
              img.onload = function () {
                let data = self.compress(img, Orientation);
                self.headerImage = data;
                // self.postImg();
              };
            }
          };
        }
      },
      postImg() {
        this.upload();
        // this.$emit('upload', this.headerImage, this.id);
        // this.$emit('input', this.headerImage);
        // this.$refs.avatar.style.background = `url(${this.headerImage})no-repeat center/contain`
      },
      rotateImg(img, direction, canvas) {
        // 最小与最大旋转方向，图片旋转4次后回到原方向
        const minStep = 0;
        const maxStep = 3;
        if (img == null) return;
        // img的高度和宽度不能在img元素隐藏后获取，否则会出错
        let height = img.height;
        let width = img.width;
        let step = 2;
        if (step == null) {
          step = minStep;
        }
        if (direction === 'right') {
          step++;
          // 旋转到原位置，即超过最大值
          step > maxStep && (step = minStep);
        } else {
          step--;
          step < minStep && (step = maxStep);
        }
        // 旋转角度以弧度值为参数
        let degree = step * 90 * Math.PI / 180;
        let ctx = canvas.getContext('2d');
        switch (step) {
          case 0:
            canvas.width = width;
            canvas.height = height;
            ctx.drawImage(img, 0, 0);
            break;
          case 1:
            canvas.width = height;
            canvas.height = width;
            ctx.rotate(degree);
            ctx.drawImage(img, 0, -height);
            break;
          case 2:
            canvas.width = width;
            canvas.height = height;
            ctx.rotate(degree);
            ctx.drawImage(img, -width, -height);
            break;
          case 3:
            canvas.width = height;
            canvas.height = width;
            ctx.rotate(degree);
            ctx.drawImage(img, -width, 0);
            break;
        }
      },
      compress(img, Orientation) {
        let canvas = document.createElement('canvas');
        let ctx = canvas.getContext('2d');
        // 瓦片canvas
        let tCanvas = document.createElement('canvas');
        let tctx = tCanvas.getContext('2d');
        let initSize = img.src.length;
        let width = img.width;
        let height = img.height;
        // 如果图片大于四百万像素，计算压缩比并将大小压至400万以下
        let ratio;
        if ((ratio = width * height / 4000000) > 1) {
          ratio = Math.sqrt(ratio);
          width /= ratio;
          height /= ratio;
        } else {
          ratio = 1;
        }
        canvas.width = width;
        canvas.height = height;
        //        铺底色
        ctx.fillStyle = '#fff';
        ctx.fillRect(0, 0, canvas.width, canvas.height);
        // 如果图片像素大于100万则使用瓦片绘制
        let count;
        if ((count = width * height / 1000000) > 1) {
          count = ~~(Math.sqrt(count) + 1); // 计算要分成多少块瓦片
          //            计算每块瓦片的宽和高
          let nw = ~~(width / count);
          let nh = ~~(height / count);
          tCanvas.width = nw;
          tCanvas.height = nh;
          for (let i = 0; i < count; i++) {
            for (let j = 0; j < count; j++) {
              tctx.drawImage(
                img,
                i * nw * ratio,
                j * nh * ratio,
                nw * ratio,
                nh * ratio,
                0,
                0,
                nw,
                nh
              );
              ctx.drawImage(tCanvas, i * nw, j * nh, nw, nh);
            }
          }
        } else {
          ctx.drawImage(img, 0, 0, width, height);
        }
        // 修复ios上传图片的时候 被旋转的问题
        if (Orientation !== '' && Orientation !== 1) {
          switch (Orientation) {
            case 6: // 需要顺时针（向左）90度旋转
              this.rotateImg(img, 'left', canvas);
              break;
            case 8: // 需要逆时针（向右）90度旋转
              this.rotateImg(img, 'right', canvas);
              break;
            case 3: // 需要180度旋转
              this.rotateImg(img, 'right', canvas); // 转两次
              this.rotateImg(img, 'right', canvas);
              break;
          }
        }
        // 进行最小压缩
        let ndata = canvas.toDataURL('image/jpeg', 0.1);
        tCanvas.width = tCanvas.height = canvas.width = canvas.height = 0;
        return ndata;
      }
    },
    mounted() {
      this.getCosCredential();
      this.user = this.$route.query;
    }
  };
</script>

<style scoped>
  .file {
    position: relative;
    display: inline-block;
    background: #D0EEFF;
    border: 1px solid #99D3F5;
    border-radius: 5px;
    overflow: hidden;
    color: #1E88C7;
    text-decoration: none;
    top: -0.6rem;
    line-height: 2rem;
  }

  .file input {
    position: absolute;
    right: 0;
    top: 0;
    opacity: 0;
  }

  .file:hover {
    background: #AADFFD;
    border-color: #78C3F3;
    color: #004974;
    text-decoration: none;
  }

  .photoTips {
    text-align: left;
    width: 80%;
    margin: auto;
    font-size: 1.6rem;
    line-height: 4rem;
    color: #767676;
    color: rgba(0, 0, 0, 1);
  }

  .cameraIcon {
    width: 80%;
    text-align: left;
    margin: 2rem auto 0;
  }
</style>
